1. Field of the Invention
The present invention relates to levels for use in masonry, carpentry or in many other fields, such as architecture and interior design. More particularly, the present invention is directed toward an adjustable plumb level having a rotational, replaceable leveling mechanism.
2. Description of the Related Art
Adjustable levels have been known for a considerable time, but these levels lacked the necessary versatility to be used for long periods of time as either a plumb or a level. This required that the person using both levels and plumbs have more than just a single piece of equipment, and replace this equipment at fairly regular intervals.
For example, Jay in U.S. Pat. No. 1,703,006 suggested a spirit level that included a vial, which could be slightly tipped by an adjustment mechanism that would allow the bubble in all levels to become centered. However, Jay suggests that a curved vial be used, which is not useful when the level is turned 90.degree.. Even though the vial may be tilted slightly to level the vial, there is not enough clearance within the gap where the vial is positioned to allow the vial to tip more than a few degrees. Further, the device disclosed by Jay includes a large number of parts to make the level operable. This is disadvantageous, especially if any of the parts should fail and need replacement.
Walker, in U.S. Pat. No. 1,380,611 also discloses a level. Walker mounts a vial with an enlarged center tightly within the beam making up the level. Thus, only minor adjustments are possible to the vial. Further, the device disclosed by Walker is only meant for use in a horizontal manner, and not in a vertical manner. It is possible that Walker intended the vial to be located in either a horizontal or a vertical position, but not in both positions using the same level.
Thus, the prior art is not capable of reversing itself and being used in a horizontal or a vertical position. Further, the prior art that is adjustable over the largest range requires use of many parts.
Due to the inherent inaccuracies of levels and plumbs, it is not uncommon for buildings to be built slightly askew. Minor errors in construction will force the next person that builds an adjacent or above structure to build the adjacent structure also at a slight tip to compensate for the skew in the first building or part. Thus, it is desirable to have an adjustable level that can be calibrated for perfect level or plumb and can be used in either a vertical or a horizontal position, i.e. as either a plumb or a level, without requiring the use of a great number of parts.